ArtB
2)If you move it to the state-level how does that simplify the statutes?
That is the crux. I feel like most businesses actually don't produce enough value to justify their own existence and therefore require below cost-of-living wages to keep them afloat.
The parts that for me made the job bearable. The rest is legacy support for CRUD apps. The office is a perk for people with few other outlets.
Also, a close family friend was given 6 months to 3 years to live when her cancer spread through her body. It's been 10 years. She is getting sicker and sicker and on chemo the whole time, but she is still managing to attend the odd family function when she is feeling up to it.
This shit isn't a game, these are peoples lives and we need to make sure they can live it even if it means a few less unicorn start ups.
The domain's job is to represent and encapsulate valid transformations in the domain. If it's not valid within the domain then it doesn't belong in it. If you get a well-formed XML file that has -7 as a social security number, that is not something that your domain has to deal with. It should be caught by the corruption layer. It's not a valid value for your domain. Where I work we regularily build an import domain that allows users to see all the invalid data and manually correct it before allowing it into the rest of the system. Once I have an instance of a Person object I should be able to trust that it is sane.
> The third, from the experience I have, is a big flashy "no no".
It depends; I'd say it's on a case-by-case. Doing a read can be much more acceptable than a write. It's all about trade-offs at that point, but the benefit of knowing "if I have an instance I know that it is sane" means you don't need to litter your code with guards and that pays dividends in maintenance and bugs and agility and testability and, yes, even performance. A big factor is the cost of load. I usually work on low-load (~14 concurrent users) high-importance systems (eg global pricing management) where correctness is at a premium and we usually have system resources to spare. YMMV. As I said: it depends.
These are two different concepts I feel you are mixing up. An object may be valid, but that doesn't mean it's valid for all operations. For example there is basic validation that a file object is valid if it exists, but if you only have read access to it .append("foo") will fail on it. But it's still a valid file. Your constructor should be checking for the first kind of validity, and your methods for the second.
> What if you receive, from a webservice or something, a valid object format-wise but invalid from the business rule perspective?
That is what you need an [anti-corruption layer](http://www.markhneedham.com/blog/2009/07/07/domain-driven-de...) for. The object makes sense within that other services domain but not within yours. That domain may be closely related to yours, but it isn't you. You need a separate object for that (a simple struct ought to suffice usually). Then you act as a gatekeeper only allowing conforming objects into your system. Basically filter out the shit, and make sure if it makes it past your gate it is clean. Otherwise you might want to use the [state pattern](https://en.wikipedia.org/wiki/State_pattern) to allow for different validation rules of the same object (eg legacy accounts might not have an email address but all new ones must).
> What if there's some info in the database that would allow or not you to construct the object the way you need? You would go to the database and check the info in your constructor?
This is touchy. Sometimes, if it's important enough then yes. Sometimes you can code around it (eg having case numbers auto-generated at time of persistence). Other times you bite the bullet. Other times you rearchitect the data (storing it in memory to do the check quickly). Or as a last resort, except it as a compromise and start coding up some roll-back functionality. Aim for the ideal, and know when to step backwards towards the practical: that is the art of software development.
Uhm for Navicat you need to buy a different license for each database and operating system you use. Where I work we use both SQL Server and MySQL and I use three different computers with different operating systems. JetBrains terms are much friendlier.
I find this _deliciously_ ironic since that is the position most students have towards mathematics in general (replace "calculations" with "anything relevant in their lives").
I'm of the opinion that this is a reason to discourage the growth of small businesses. They are too small to absorb shocks like pregnancy or family emergency that contribute to the well-being of a society.
Is there a name for the logical fallacy where one knowingly misrepresents true statements to suggests things that aren't true? (ie that only unions used violence or had criminal ties).
I believe this has been solved in intuitionistic logic (http://en.wikipedia.org/wiki/Intuitionistic_logic). If you don't except the law of the excluded middle and require constructive proofs you avoid many of these shenanigans.